RECON: TNO occultation with 99OD4

Event between 99OD4 and star GA0860:16795275 with event index number of 2438911

Geocentric closest approach at 2023/12/17 21:31:40 UTC

J2000 position of star is 22:04:11.5 -03:47:12
Equinox of date position of star is 22:05:19.6 -03:40:48
Stellar brightness G=16.4, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 12 degrees from the moon. Moon is 29% illuminated.
TNO apparent brightness V=23.7

TNO is 42.8 AU from the Sun and 43.1 AU from the Earth.
The TNO is moving 16.8 km/sec on the sky relative to the star, or, 1.9 arcsec/hr.
The 1-sigma error in the time of the event is 348 seconds.
The 1-sigma cross-track error in the shadow position is 4317 km.

The TNO has an absolute magnitude Hv=7.2
Diameter=218.8 km assuming a 5% albedo -- 12.9 sec chord
Diameter=89.3 km assuming a 30% albedo -- 5.3 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 
 
 

Star training set for 99OD4, (2023/12/17 21:32UT)
Object            RA         Dec     mag  sep  mel
Fomalhaut      22:58:58.1 -29:29:41  1.2 28.77  17
Markab         23:05:57.4 +15:20:05  2.5 24.20  32
PPM 205831     22:00:09.9 -04:15:33  6.2  1.44  11
PPM 205962     22:07:16.9 -02:59:20  8.0  0.82  12
PPM 205936     22:05:41.8 -03:36:16  9.7  0.09  12
99OD4          22:05:26.2 -03:40:11 16.4        12
Positions are for equinox of date

Azimuth is measured in degrees eastward from north. North is at an azimuth of 0, due East is at an azimuth of 90 degrees, due South is 180, and due West is 270.

Do not use the listing below for the RECON CPC 1100 telescopes. This is provided for other non-team facilities.

Star training set for 99OD4, (2023/12/17 21:32UT)
Object            RA         Dec     mag  sep  mel
Fomalhaut      22:57:39.6 -29:37:24  1.2 28.77  17
Markab         23:04:45.8 +15:12:18  2.5 24.20  32
PPM 205831     21:58:55.0 -04:22:29  6.2  1.44  11
PPM 205962     22:06:02.4 -03:06:23  8.0  0.82  12
PPM 205936     22:04:27.1 -03:43:17  9.7  0.09  12
99OD4          22:04:11.5 -03:47:12 16.4        12
Positions are for J2000

Event circumstances last updated at 2021/10/27 00:06:49 UT

Marc W. Buie, Southwest Research Institute

RECON